混凝剂中的铝形态对黄河水源水中出水余铝的影响  

Effects of Aluminum form in coagulant on residual Aluminum in effluent of the source water of Yellow River

作　　者：吴福雨 李能能 樊小东 马彪 郭欣 尹志昌 徐慧[2] 吴俊辉 WU Fuyu;LI Nengneng;FAN Xiaodong;MA Biao;GUO Xin;YIN Zhichang;XU Hui;WU Junhui(Ningxia Great Wall Water Co.Ltd.,Yinchuan 750000,China;State Key Laboratory of Environmental Aquatic Chemistry,Research Center for Eco-Environmental Sciences,Chinese Academy of Sciences,Beijing 100085,China;Yangtze River Delta Research Center for Eco-Environmental Sciences,Yiwu 321000,China)

机构地区：[1]宁夏长城水务有限责任公司,银川750000 [2]中国科学院生态环境研究中心环境水质学国家重点实验室,北京100085 [3]长三角(义乌)生态环境研究中心,金华321000

出　　处：《环境工程学报》2022年第12期3926-3934,共9页Chinese Journal of Environmental Engineering

基　　金：国家自然科学基金重点项目(52030003)。

摘　　要：铝系混凝剂是应用最广泛的无机混凝剂,改善混凝剂中的铝形态可有效提高混凝效果,但其在净水过程中产生的余铝对人体健康及输水过程具有显著的影响。本文研究了氯化铝(AlCl_(3))和高聚十三铝(Al_(13))2种混凝剂在处理黄河上游水源水时的混凝过程,结合出水中的溶解态及不同分子质量余铝含量、有机物紫外吸光度(UV254)、pH、浊度、有机物种类及含量和絮体特性的变化趋势,探究混凝剂中的铝形态对混凝过程的影响。结果表明,在实验投加量范围内,当Al_(13)做混凝剂时,出水余铝质量浓度均低于0.2 mg·L^(-1)。Al_(13)具有较高的形态稳定性,在混凝过程中对出水pH影响较小。絮体粒度随混凝剂投加量的增加而增加,Al_(13)投加量达到0.08 mmol·L^(-1)时絮体粒度下降(强度因子由于静电排斥作用而下降)。在不同投加量下,使用AlCl_(3)做混凝剂时出水余铝均高于Al_(13)体系,且在不同投加量下AlCl_(3)体系出水余铝中小于1000 Da的余铝占比最大。Al_(13)对富里酸和腐殖酸的去除效果优于AlCl_(3),且AlCl_(3)在较高投加量下才能实现水中有机物的有效去除。Al-based coagulants are the most widely used inorganic coagulants,and the optimized Al species can improve the coagulation performances,but the residual aluminum produced in the treatment process has significant impacts on human health and water transport process.In this study,Al_(13)and AlCl_(3)were used as coagulants to treat the source water of Yellow River,and the coagulation process was investigated.Combined with variations of the concentration of dissolved residual aluminum and residual aluminum with different molecular weights,UV254,pH,turbidity,concentration or species of organic matter and flocs characteristics,effects of aluminum species on residual aluminum and coagulation performances were investigated.The results showed that when Al_(13)was used as coagulant,the mass concentration of residual aluminum was lower than 0.2 mg·L^(-1),and the concentration was less affected by the dosage.Due to its high stability of species,Al_(13)had less effects on pH of effluent during coagulation process.The particle size of flocs increased with the increase of coagulant dosage,but it decreased when the dosage of Al_(13)reached 0.08 mmol·L^(-1)(the strength factors decreased due to electrostatic repulsion).The residual aluminum using AlCl_(3)as coagulant was higher than that in Al_(13)system at different dosages,and the proportion of residual aluminum with molecular weight lower than 1000Da in AlCl_(3)was the largest in AlCl_(3)system.The removal efficiency of fulvic acid and humic acid using Al_(13)was better than using AlCl_(3),the latter could achieve high effective removal of organics in water at high dosages.

关 键 词：混凝 Al_(13) AlCl_(3) 余铝 絮体 

分 类 号：X703[环境科学与工程—环境工程]